Gemini 3.1 Ultra vs Mistral Large 3

Head-to-head technical comparison of intelligence, capabilities, and API pricing.

Gemini 3.1 Ultra
Google
AI Mastery Index92.5
LMSYS Arena1480
Technical (MMLU-Pro)92.5%
Cost per 1M Tokens$20
Mistral Large 3
Mistral
AI Mastery Index89.2
LMSYS Arena1430
Technical (MMLU-Pro)89.2%
Cost per 1M Tokens$0.5

Which should you use?

Gemini 3.1 Ultra leads on the composite index by 3.3 points (92.5 vs 89.2).

Cost is the sharper difference: Gemini 3.1 Ultra is 40x the input price of Mistral Large 3 ($20 against $0.5 per 1M), so at volume the choice is usually decided by budget rather than benchmarks.

Pick Gemini 3.1 Ultra when

  • Higher composite index — 92.5 against 89.2, a gap of 3.3 points.
  • Ahead on Arena Elo by 50 points (1480 vs 1430), which is outside the board's published confidence intervals.
  • Stronger on MMLU-Pro: 92.5% against 89.2%.

Pick Mistral Large 3 when

  • Cheaper input tokens — $0.5 against $20 per 1M, so Gemini 3.1 Ultra costs 40x as much to feed.
  • Better value per point of measured capability: $0.006 per index point against $0.216.

Value per point of measured capability, at list input pricing: Mistral Large 3 $0.006 · Gemini 3.1 Ultra $0.216 per index point. Run your own token mix through the token cost calculator — a comparison at list price ignores caching and batch discounts, which move real bills more than this gap does.

Our reporting on Google and Mistral